Field of the Invention
The invention is directed to infusion set adhesive systems for attachment of an infusion set to a wearer's body using a patch.
Description of the Related Art
An infusion set is a device attached to a wearer's body to deliver a medication from an infusion pump to a subcutaneous site on the wearer's body. The infusion set generally comprises a hub, or base, bearing an infusion cannula inserted into the infusion site on the wearer's body, and a tube connecting the cannula to the infusion pump. The hub is attached to a patch which is attached to the wearer's body with an adhesive system such that the infusion set can be removed and replaced every several days.
Many variations on the adhesive patch are practiced in the art, but in general, the adhesive patch comprises a backing layer having a central area receiving the hub and cannula, a layer of adhesive adjacent the backing layer which faces the wearer, and a release liner over the adhesive to prevent the adhesive from becoming contaminated before use. Adhesives for this purpose are typically provided commercially already applied to a backing layer, with a release liner covering the adhesive to prevent the adhesive from being contaminated prior to use.
One conventional backing layer material for the adhesive is nonwoven polyester. The nonwoven provides good structural integrity, but poor water resistance. Also, the nonwoven material has a tendency to curl back at the edges and peel off. Polyurethane sheet, on the other hand, another conventional backing layer material, has good water resistance and conforming characteristics for adhesion, but it can be too flexible, making it difficult for the user to handle without the material folding over and sticking to itself. Thus, another object of the invention is to maximize the performance characteristics of backing layer materials for an infusion set patch.
The adhesive systems known in the art are sensitive to body perspiration which wets and degrades the pressure sensitive adhesive. It is another object of the invention to address the problem whereby body perspiration degrades the performance of the infusion set adhesive system.
The patches sold with infusion sets according to the prior art are typically circular, and in general have not been optimized for attachment to different parts of the body. Thus, a further object of the invention is to provide a product line from which the user can select an adhesive system based on the adhesion site on the body and activity.
The infusion sets known in the prior art are sold with only one choice of peel strength. The inventors herein have recognized that the use of infusion sets has become more nuanced, such that it would be a desirable advance in the art to provide infusion set patches optimized for different end use patterns. Thus, different users could select infusion sets from a product line offering patches with different adhesion strength for different use patterns.